Forest Biome Research Articles

A new species and new records of the spider genus Dubiaranea (Araneae, Linyphiidae) from southern Brazil and Uruguay, with an analysis of the potential distribution of the species

Dubiaranea magatama Cajade, Hagopián & Rodrigues n. sp. is described from Uruguay, and southern Brazil based on males and females from several types of native forests, and a potential distribution for this species is modeled. The predicted model for this species indicates a Pampean province and southern Atlantic Forest biome distribution. Three variables contributed significantly to the model with positive influence: the spatial component, the proximity to large rivers, and the tree cover. Also, we provide new records of Dubiaranea difficilis (Mello-Leitão 1944) for Uruguay and a model of its potential distribution was performed. It showed that tree cover, the proximity to large rivers, the spatial component and precipitation/evapotranspiration constraints were recovered for the model with positive influence, expanding the potential distribution area previously proposed.

Vitisma coriacea sp.n. (Insecta: Dictyoptera) from the mid-Cretaceous in northern Myanmar, first record of the genus in amber

The genus Vitisma Vršanský, 1999 is characterised by a shield-like, convex pronotum with transverse margins, scleroritized forewings with sometimes white macula, long clavus and rather simplified venation (simple Sc, straight and expanded M veins, CuA narrow and branched, A simple, R reaching apex). The hindwing venation is similar to the Blattulidae with a distinct pterostigma, but R1 is comb-like and CuA branched. The first record of Vitisma coriacea sp. n. in Burmese amber extends its palaeogeographic distribution to Gondwana, similar to other Umenocoleoidea. So far, the genus was only known from sediments in Spain, Russia, Mongolia, and possibly Japan. It also suggests that representatives of Vitisma inhabited warmer, tropical forest biomes.

Linking leaf elemental traits to biomass across forest biomes in the Himalayas

Linking leaf elemental traits to biomass across forest biomes in the Himalayas

Water Balance In Hapic Cambisols Under Forest And Pasture In The Bonfim Watershed: Mountainous Region Of Rio De Janeiro State

Objective: To estimate the water volumes of the main components of BH in a Haplic Cambisol in forests and pastures in the Bonfim River basin, mountainous region of RJ. Theoretical framework: The water balance (BH) accounts for the volumes of water input and output in a given space (Haplic Cambisols under forests and pastures). Method: The study period was 01/01/2000 and 12/31/2019. The HYDRUS-1D model was used to estimate water volumes in BH. Pedotransfer functions were used to determine the physical water parameters of water retention and conduction in the soil. The daily precipitation and evapotranspiration data were considered upper boundary conditions, and the lower boundary conditions were considered free drainage. Water absorption by the roots was considered as the additional factor (Sink factor) in the soil water mass balance. Results and conclusion: The average annual precipitation was 1462 mm and the potential evapotranspiration was 1026 mm. In lhe area under pastures: 83%, 7% and 9% of the total precipitated and percolated, transpired and evaporated, respectively. In areas under forests: these values were 43%, 51% and 6%. In the dry season, evapotranspiration was 20% of the total precipitation in the forest area and 8% in the pasture areas. Percolation in the dry season was 17% of the total precipitation in the pasture and 7% in the forest. In the rainy season the percolated values were 66% in the pasture and 36% in the forest. Implications of the research: Knowing the volumes of water in the components of the BH can help in decisions regarding the organization of land use and cover systems in basins of the Atlantic Forest biome. Changing soil use and cover systems alters the volumes of water percolated or evapotranspired. Originality/value: Estimating the water volumes in the BH components in pasture and forest allows predicting the effects of climate change and land use and their consequences.

Spatial phylogenetics of Fagales: Investigating drivers of temperate forest distributions

AbstractAimQuantifying the phylogenetic diversity of temperate trees is essential for understanding the processes that have shaped the modern distribution of temperate broadleaf forest and other major forest biomes. Here, we focus on Fagales, an iconic member of forests worldwide, to uncover global diversity and endemism patterns and investigate the distribution of root nodule symbiosis (RNS), an important morphological specialisation in this clade, as a key factor behind these patterns.LocationGlobal.TaxonFagales.MethodsWe combined phylogenetic data covering 60.2% of living species, fine‐scale distribution models covering 90% of species, and nodulation data covering all species to investigate the distribution of species richness and phylogenetic diversity at fine spatial scales compared to the distribution of RNS. We identify abiotic environmental factors associated with RNS and with Fagales diversity in general.ResultsWe find the highest species richness in temperate east Asia, eastern North America, and equatorial montane regions of Asia and Central America. By contrast, relative phylogenetic diversity (RPD) is highest at higher latitudes, where RNS also predominates. We found a strong spatial structuring of regionalisations of Fagales floras, reflecting distinct Northern and Southern Hemisphere floras (except a unique Afro‐Boreal region), each with distinct RNS‐environment relationships.Main ConclusionsAlthough species richness and phylogenetic regionalisation for Fagales accord well with traditional biogeographic concepts for temperate forests, this is not the case for RPD. RNS is almost universal in the highest RPD regions, which may reflect ecological filtering promoting RNS in these regions. Our results highlight the utility of global‐scale, clade‐specific spatial phylogenetics and its utility for understanding drivers of diversity in species‐rich clades.

Patterns and trends in the spatial heterogeneity of land surface phenology of global forests

Land-surface phenology is a widely used indicator of how terrestrial ecosystems respond to environmental change. The spatial variability of this plant functional trait has also been advocated as an indicator of the functional composition of ecosystems. However, a global-scale assessment of spatial patterns in the spatial heterogeneity of forest phenology is currently lacking. To address this knowledge gap, we developed an index based on satellite retrievals and used it to quantify phenological diversity across global forest biomes. We show that there is considerable variation in phenological diversity among biomes, with the highest overall levels occurring in arid and temperate regions. An analysis of the drivers of the spatial patterns revealed that temperature-related factors primarily determine the variation in phenological diversity. Notably, temperature seasonality and mean annual temperature emerged as the most significant variables in explaining this global-scale variability. Furthermore, an assessment of temporal changes over an 18-year period revealed strong climate-driven shifts of phenological diversity in boreal and arid regions, suggesting that there may be an ongoing widespread homogenisation of land surface phenology within forest ecosystems. Our findings ultimately contribute to the development of a novel Essential Biodiversity Variable, which may enable scientists and practitioners to quantify the functional composition of ecosystems at unprecedented spatial and temporal scales.

Unraveling the genetic diversity of Ceiba pubiflora (Malvaceae) in isolated limestone outcrops: Conservation strategies.

Seasonally Dry Tropical Forests (SDTFs) located on limestone outcrops are vulnerable to degradation caused by timber logging and limestone extraction for cement production. Some of these forests represent the last remnants of native vegetation cover, functioning as isolated islands. Ceiba pubiflora (Malvaceae) is a tree frequently found on limestone outcrops in the central region of Brazil. This study aimed to evaluate the genetic diversity and identify suitable populations for the establishment of Management Units (MUs) for conservation. Inter-simple sequence repeat markers were employed to assess the genetic diversity in ten populations sampled from the Caatinga, Cerrado, and Atlantic Forest biomes. The species exhibited substantial genetic diversity (HT = 0.345; PLP = 97.89%). Populations SAH, JAN, and MON demonstrated elevated rates of polymorphic loci (> 84.2%) along with notable genetic diversity (He > 0.325). Additionally, these populations were the primary contributors to gene flow. The analysis of molecular variance (AMOVA) indicated that most genetic variation occurs within populations (91.5%) than between them. In the Bayesian analysis, the ten populations were clustered into five groups, revealing the presence of at least three barriers to gene flow in the landscape: 1) the Central Plateau or Paranã River valley; 2) near the Espinhaço mountains or the São Francisco River valley; and 3) around the Mantiqueira mountain range, Chapada dos Veadeiros plateau, and disturbed areas. A positive and statistically significant correlation was observed between genetic (θB) and geographic distances (r = 0.425, p = 0.008). Based on these findings, we propose the establishment of Management Units in Minas Gerais state, encompassing the (1) southern region (MIN population), (2) central region (SAH population), and (3) north region (MON population), as well as in Goiás state, covering the (4) Central Plateau region. These units can significantly contribute to preserving the genetic diversity of these trees and protecting their habitat against ongoing threats.

An improved method for edge detection based on neighbor distance for processing hemispheric photography

Abstract Hemisphere photos are now widely applied to provide information about solar radiation dynamics, canopy structure and their contribution to biophysical processes, plant productivity and ecosystem properties. The present study aims to improve the original ‘edge detection’ method for binary classification between sky and canopy, which works not well for closed canopies. We supposed such inaccuracy probably is due to the influence of sky pixels on their neighbor canopy pixels. Here, we introduced a new term ‘neighbor distance’, defined as the distance between pixels participated in the calculation of contrast at the edges between classified canopy and sky, into the ‘edge detection’ method. We showed that choosing a suitable neighbor distance for a photo with a specific gap fraction can significantly improve the accuracy of the original ‘edge detection’ method. We developed an ND-IS (Neighbor Distance-Iteration Selection) method that can automatically determine the threshold values of hemisphere photos with high accuracy and reproductivity. It combines the modified ‘edge detection’ method and an iterative selection method, with the aid of an empirical power function for the relationship between neighbor distance and manually verified gap fraction. This procedure worked well throughout a broad range of gap fractions (0.019–0.945) with different canopy compositions and structures, in five forest biomes along a broad gradient of latitude and longitude across Eastern China. Our results highlight the necessity of integrating neighbor distance into the original ‘edge detection’ algorithm. The advantages and limitations of the method, and the application of the method in the field were also discussed.

Amphibian conservation status in Brazil: Spatial patterns, threats, and challenges

Extinction risk assessments are valuable conservation tools, especially for sensitive groups like amphibians, which are facing escalating threats from habitat loss and degradation. In this scenario, Brazil stands out as a pivotal player in amphibian conservation due to its exceptional amphibian diversity. Between 2010 and 2014, 973 amphibian species were assessed in Brazil. More recently, from 2017 to 2018, this number increased to 1096. In this study, we (1) compare the extinction risk status of Brazilian amphibians between the 1st and 2nd assessments; (2) evaluate the reasons for changes in status; (3) identify the main threats and research recommendations; and (4) analyze the spatial patterns of threatened species in relation to protected areas and ecoregions in Brazil. Our findings reveal an increase in the number of threatened species from the first to the second assessment. The categories of Least Concern and Critically Endangered experienced the most significant increases, with 169 and 16 more species, respectively, while the count of Data Deficient species dropped by 71. The primary factor contributing to these changes is the availability of new, more precise information, affecting 134 species, or 85.4% of the cases. Threatened species are predominantly clustered within the Atlantic Forest biome, itself the most endangered biome in Brazil, hosting 46 species, or 78% of the total. Notably, one-third of threatened species in Brazil do not inhabit protected areas and thus require immediate conservation attention. While substantial progress has been made in understanding Brazilian amphibians in recent years, an urgent need persists for fundamental research. This research should encompass taxonomy, natural history, and the evaluation of threat impacts, providing a robust foundation for more effective conservation efforts concerning this group.

Thermal, water, and land cover factors led to contrasting urban and rural vegetation resilience to extreme hot months.

With continuing global warming and urbanization, it is increasingly important to understand the resilience of urban vegetation to extreme high temperatures, but few studies have examined urban vegetation at large scale or both concurrent and delayed responses. In this study, we performed an urban-rural comparison using the Enhanced Vegetation Index and months that exceed the historical 90th percentile in mean temperature (referred to as "hot months") across 85 major cities in the contiguous United States. We found that hot months initially enhanced vegetation greenness but could cause a decline afterwards, especially for persistent (≥4 months) and intense (≥+2 °C) episodes in summer. The urban responses were more positive than rural in the western United States or in winter, but more negative during spring-autumn in the eastern United States. The east-west difference can be attributed to the higher optimal growth temperatures and lower water stress levels of the western urban vegetation than the rural. The urban responses also had smaller magnitudes than the rural responses, especially in deciduous forest biomes, and least in evergreen forest biomes. Within each biome, analysis at 1 km pixel level showed that impervious fraction and vegetation cover, local urban heat island intensity, and water stress were the key drivers of urban-rural differences. These findings advance our understanding of how prolonged exposure to warm extremes, particularly within urban environments, affects vegetation greenness and vitality. Urban planners and ecosystem managers should prioritize the long and intense events and the key drivers in fostering urban vegetation resilience to heat waves.

Ideas and perspectives: Sensing energy and matter fluxes in a biota-dominated Patagonian landscape through environmental seismology – introducing the Pumalín Critical Zone Observatory

Abstract. The coastal temperate rainforests (CTRs) of Chilean Patagonia are a valuable forest biome on Earth given their prominent role in biogeochemical cycling and the ecological value and dynamics of surface processes. The Patagonian CTRs are amongst the most carbon-rich biomes on Earth. Together with frequent landscape disturbances, these forests potentially allow for episodic and massive release or sequestration of carbon into and from the atmosphere. We argue that, despite their particular biogeographic, geochemical, and ecological roles, the Patagonian CTRs in particular and the global CTRs in general are not adequately represented in the current catalog listing critical zone observatories (CZOs). Here, we present the Pumalín CZO as the first of its kind, located in Pumalín National Park in northern Chilean Patagonia. We consider our CZO a representative end-member of undisturbed ecosystem functioning of the Patagonian CTRs. We have identified four core research themes for the Pumalín CZO around which our activities circle in an integrative, quantitative, and generic approach using a range of emerging techniques. Our methodological blend includes an environmental seismology that also fills a critical spatiotemporal scale in terms of monitoring critical zone and surface processes with a minimum intervention in those pristine forests. We aim to gain quantitative understanding of these topics: (1) carbon sink functioning; (2) biota-driven landscape evolution; (3) water, biogeological, and energy fluxes; and (4) disturbance regime understanding. Our findings highlight the multitude of active functions that trees in particular and forests in general may have on the entire cascade of surface processes and the concomitant carbon cycling. This highlights the importance of an integrated approach, i.e., “one physical system”, as proposed by Richter and Billings (2015), and accounts for the recent advances in pushing nature conservation along the Chilean coast.

ORGANIC CARBON DYNAMICS IN SOIL FROM FOREST FRAGMENTS IN THE ATLANTIC FOREST AND CERRADO BIOMES

The study aimed to evaluate changes in organic carbon concentrations and oxidizable fractions of soil organic matter in and around forest fragments in the Atlantic Forest (AF) and Cerrado (CE) biomes. Soil samples were collected from four forest fragments, two in the AF and two in the CE, in which three internal points were sampled: edge (ED), half radius (HR), and center (CF), as well as a point in the surroundings; no-tillage (NT) and permanent pasture (PP) in AF and CE, respectively. The total organic carbon (TOC) content and the carbon of the oxidizable fractions (F1, F2, F3, F4) were quantified. The CF of the AF forest fragments showed the highest TOC and C contents in the labile fractions F1 and F2 (the fraction most sensitive to changes in the environment), with the lowest contents in the ED. In the CE, the fragments showed different TOC contents and dynamics, with the highest TOC and F1 contents in the HR and the lowest in the CF of fragment 1, while in fragment 2 the highest TOC contents were in the CF and the lowest in the ED and HR, but they did not differ in the contents of the F1 and F2 fractions. The lower levels of TOC and C labile in the ED of the fragments are due to the negative interference of the edge effect, which, through abiotic factors, has modified the species composition and structure of the plant community, altering the dynamics of C storage and emission.

Palynology of Huberia (Melastomataceae: Cambessedesieae): diversity and taxonomic implications

Huberia DC. is a genus belonging to the family Melastomataceae, which comprises 37 species distributed in vegetation formations of the Amazon Forest and Andes complex and the Atlantic Forest biome. Recent phylogenetic studies have modified the circumscription of the genus to include the genera Behuria Cham. and Dolichoura Brade. Furthermore, the genus was placed in the new tribe Cambessedesieae, together with the genera Cambessedesia DC. and Merianthera Kuhlm. In view of the relevant contribution of palynology to taxonomic and phylogenetic studies, this study aimed to expand the palynological knowledge of Huberia. Samples from 22 species were obtained from specimens deposited in the herbaria of the Rio de Janeiro Botanical Garden (RB), National Museum/UFRJ (R), Municipal Botanical Museum of Curitiba (MBM), and Federal University of Paraná (UPCB). Flower buds were acetolysed and used to prepare pollen sediment slides. Slides were mounted with glycerinated gelatin and analyzed and photographed under a light microscope. The results showed pollen grains in monads, small, varying in shape from prolate-spheroidal to subprolate; heteroaperturate (colporate and pseudocolpate), tricolporate, with a small, very small, or non-existent polar area in syncolporate pollen; colpi long or very long and narrow, endoaperture lalongate with median constriction in most species and lolongate in others; exine perforate, rugulate, or striate microreticulate and the sexine thicker than the nexine. Based on the findings of this study, it is concluded that palynological characters provide information for the taxonomy of the group.

The role of dispersal limitation in the forest biome shifts of Europe in the last 18,000 years

AbstractAimHow the ability of plants to move towards newly favourable habitats (dispersal limitation) impacts the change of biome distribution and transition under fast climate warming is still debated. Analysing vegetation change in the past may help to clarify the relative importance of underlying ecological processes such as climate, biotic interactions, and dispersal. In this study, we investigated how dispersal limitation affected the distribution of European forests in the last 18,000 years.LocationSouthern and Central Europe.TaxonSpermatophyta.MethodsUsing the LPJ‐GM 2.0 model (an extension of LPJ‐GUESS), we simulated European vegetation from the end of the Last Glacial Maximum (18.5 ka) to the current time (0 ka). Using biome reconstructions from pollen data as reference, we compared the performance of two dispersal modes: with no migration constraints or seed limitation (free dispersal mode), and with plant establishment depending on seed dynamics and dispersal (dispersal limitation mode).ResultsThe model run, including migration processes, was better at capturing the post‐glacial expansion of European temperate forests (and the longer persistence of boreal forests) than the setting assuming free dispersal, especially during periods of rapid warming. This suggests that a number of (temperate) tree taxa experienced delayed occupancy of climatically suitable habitats due to a limited dispersal capacity, i.e., post‐glacial migration lags.Main ConclusionsOur results show that including migration processes in model simulations allows for more realistic reconstructions of forest patterns under rapid climate change, with consequences for future projections of carbon sequestration and climate reconstructions with vegetation feedback, assisted migration and forest conservation.

Ranavirus and helminth parasite co-infection in invasive American bullfrogs in the Atlantic forest, Brazil

Emerging infectious diseases threaten amphibian species across the globe. In Brazil, the American bullfrog (Aquarana catesbeiana) is a highly invasive species that can potentially transmit parasites and pathogens to native amphibians. This is the first assessment of co-infection of Ranavirus and helminth macroparasites in invasive populations of bullfrogs in South America. We collected, measured, and euthanized 65 specimens of A. catesbeiana sampled from 9 sites across three states of Brazil in the Atlantic Forest biome. We collected and identified helminth macroparasites and sampled host liver tissue to test for the presence and load of Ranavirus with quantitative PCR. We documented patterns of prevalence, parasite load, and co-infection with generalized linear mixed models, generalized logistic regressions, and randomization tests. Most individual bullfrogs did not exhibit clinical signs of infection, but the overall Ranavirus prevalence was 27% (95% confidence interval, [CI 17–38]). Bullfrogs were infected with helminth macroparasites from 5 taxa. Co-infection of helminth macroparasites and Ranavirus was also common (21% CI [12–31]). Bullfrog size was positively correlated with total macroparasite abundance and richness, and the best-fitting model included a significant interaction between bullfrog size and Ranavirus infection status. We observed a negative correlation between Ranavirus viral load and nematode abundance (slope = −0.22, P = 0.03). Invasive bullfrogs (A. catesbeiana) in Brazil were frequently infected with both Ranavirus and helminth macroparasites, so adult bullfrogs could serve as reservoir hosts for both pathogens and parasites. However, many macroparasites collected were encysted and not developing. Coinfection patterns suggest a potential interaction between Ranavirus and macroparasites because helminth abundance increased with bullfrog size but was lower in Ranavirus infected individuals. Future studies of bullfrogs in the Atlantic Forest should investigate their potential role in pathogen and parasite transmission to native anurans.

Optimal representation of spring phenology on photosynthetic productivity across the northern hemisphere forests

Accurate simulation of the onset of spring is crucial for predicting the photosynthetic productivity of forest ecosystems. Nonetheless, the potential of phenology simulations on predictions of forest gross primary productivity (GPP) remains poorly understood, with previous studies generally focused on predicting phenology dates themselves or on limited scales. Here, we constructed a framework through the critical process of leaf growth to couple a terrestrial biosphere model—FORCCHN2 with five widely used phenology models, including one-phase (involving heat forcing), two-phase (considering chilling demand), and multi-phase models (integrating photoperiod effects) through the critical process of leaf growth. We evaluated the GPP performance from the multiple forest biomes in 74 eddy covariance (EC) sites and compared the total trends to satellite observations across the northern hemisphere forests. The predictions of the five models could reproduce 62.41–67.24 % variations of the GPP observations in all EC sites. In the deciduous broadleaf forest sites, we found the two-phase and multi-phase coupled models performed better than the one-phase coupled model. Chilling may play an essential role in controlling photosynthetic activity in deciduous broadleaf forests. Moreover, the multi-phase coupled model integrated photoperiod effects performed best at capturing GPP changes of the whole northern hemisphere forests. The predictions also showed the GPP in the northern hemisphere ranged from 21.68 to 26.06 Pg C year−1, and the total GPP showed an increasing trend. This study provides local and regional available evidence for the impact of phenology on photosynthesis with climate warming. The results highlight the necessity for enhancing understanding of the phenology factors on GPP and integrating the appropriate phenology representation to improve predictions of photosynthetic productivity for forests, especially in prediction to large scales and long-term trends.

Forest monitoring data of 45 plots across the Japanese archipelago during 1980–2021

AbstractLong‐term monitoring of forest tree communities is a basis for elucidating forest structure and dynamics and for evaluating ecosystem functions such as primary production. Because global climate change is changing forest ecosystems from the local to the global scale, it is essential to document long‐term monitoring data of forests to examine the temporal and geographical trends of forest changes. We report monitoring data of 45 forest plots (average area 0.69 ha; range 0.0325–6.25 ha) at 27 sites in Japan. These plots are situated within 32.38° N to 43.36° N and at elevations ranging from 8 to 2453 m above sea level. The forest plots include both old‐growth and secondary forests, and cover various forest biomes, such as warm‐temperate evergreen forests, temperate deciduous broadleaved forests, and boreal or sub‐alpine coniferous forests. In each plot, all living trees and lianas larger than a certain minimum size (typically 15 cm stem girth at breast height) were repeatedly measured and survival and recruitment of stems were recorded over 5–40 years (average 17.3 years). The data are presented in the format used by the Monitoring Sites 1000 Project in Japan (Ishihara et al. 2011, Ecological Research, 26, 1007–1008) and in the sample‐based Darwin Core format. This dataset expands existing open monitoring data for Japanese forests and thereby facilitates further meta‐analysis of forest community structures and changes in relation to climate change and other drivers. The complete data set for this abstract is available in electronic format in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2024-03.1/jalter-en.

Ants as Bioindicators of Habitat Conservation in a Conservation Area of the Atlantic Forest Biome

Ants are used as bioindicators because they play diverse ecological roles in terrestrial ecosystems. Their richness, abundance, and broad geographic distribution allow these insects to be used to predict the conditions of environmental conservation. This study aimed to evaluate the bioindicator potential of the ant fauna in Parque Estadual do Turvo, Rio Grande do Sul. Sampling was carried out in two events, in January and November of 2019, using soil and canopy pitfall traps, sardine baits, glucose baits, an entomological umbrella, and a sweeping net. We verified the association of ant species to the sampled strata (soil and leaf litter and vegetation) through an Indicator Species Analysis (ISA) and Principal Component Analysis (PCA). We identified 157 species belonging to 32 genera and eight subfamilies. The subfamily with the most outstanding richness was Myrmicinae, with 70 species, followed by Formicinae, with 40 species. The richest genera in the samples were Camponotus (S = 29), Pheidole (S = 23), and Linepithema (S = 11). Overall, 58 species occurred exclusively in the soil and leaf litter stratum and 23 in the arboreal stratum. Nine species had a significant indication value for the sampled strata, seven for soil and leaf litter, and two for the arboreal strata. The results show the potential of ant fauna as a basis for environmental impact studies and management and conservation plans in the southern Atlantic Forest biome.

Biodiversity mitigates drought effects in the decomposer system across biomes

Multiple facets of global change affect the earth system interactively, with complex consequences for ecosystem functioning and stability. Simultaneous climate and biodiversity change are of particular concern, because biodiversity may contribute to ecosystem resistance and resilience and may mitigate climate change impacts. Yet, the extent and generality of how climate and biodiversity change interact remain insufficiently understood, especially for the decomposition of organic matter, a major determinant of the biosphere-atmosphere carbon feedbacks. With an inter-biome field experiment using large rainfall exclusion facilities, we tested how drought, a common prediction of climate change models for many parts of the world, and biodiversity in the decomposer system drive decomposition in forest ecosystems interactively. Decomposing leaf litter lost less carbon (C) and especially nitrogen (N) in five different forest biomes following partial rainfall exclusion compared to conditions without rainfall exclusion. An increasing complexity of the decomposer community alleviated drought effects, with full compensation when large-bodied invertebrates were present. Leaf litter mixing increased diversity effects, with increasing litter species richness, which contributed to counteracting drought effects on C and N loss, although to a much smaller degree than decomposer community complexity. Our results show at a relevant spatial scale covering distinct climate zones that both, the diversity of decomposer communities and plant litter in forest floors have a strong potential to mitigate drought effects on C and N dynamics during decomposition. Preserving biodiversity at multiple trophic levels contributes to ecosystem resistance and appears critical to maintain ecosystem processes under ongoing climate change.

Native peccaries activity patterns and temporal overlap with wild boar in the southern Brazilian Atlantic Forest

ABSTRACT We analyzed long-term camera-trap data from Protected Areas in the Brazilian Atlantic Forest to study activity patterns of coexisting peccary species (Tayassu pecari and Dicotyles tajacu) and the exotic wild boar (Sus scrofa). The highest pattern overlap was between D. tajacu and S. scrofa (Δ1 = 0.78), followed by T. pecari and S. scrofa (Δ1 = 0.64), and the lowest between D. tajacu and T. pecari (Δ1 = 0.61). In the presence of feral pigs, collared peccary activity exhibited two distinct peaks, occurring in the late evening and early morning. When coexisting with white-lipped peccaries, their activity peaks early in the evening and again in the mid-morning, potentially enabling them to avoid overlapping with the activity peaks of white-lipped peccaries, which are distributed throughout the day. Our findings suggest a potential interference of wild boars in the temporal niche dynamics of native peccaries across various areas within the Brazilian Atlantic Forest biome. Nonetheless, we emphasize the imperative for more focused investigations at both regional micro and macro scales throughout the Atlantic Forest, specifically delving into other dimensions of the niche, such as food and habitat utilization among the three species.